Don't jump to conclusions about the hen & eggs problem - the overlay plot just normalises the three datasets. It is pretty evident, though. There is a known irregularity for global temp in the 1940s and 50s, I wonder whether they eventually agreed on the cause (volcanic activity?). Here is what the New Scientist writes about it:

Quote

The sudden drop in temperatures in 1945 now appears to be an artefact of a switch from using mainly US ships to collect sea surface temperature data to using mainly UK ships. The two fleets used a different method.

Source (69 lines of code) and data are attached; building requires MasmBasic version 10 April 2019 or later. Grateful for feedback if it looks good on other Windows versions, too (screenshot is Win7-64; WinXP works, too).

If I find the time, I will post a step-by-step example soon. The attached GlobalWarming.asc uses three different methods to load the data into numeric arrays, here are two:

To assemble this source, update MasmBasic, then extract the attached files to a temp folder on the drive where your Masm32 is installed, open the *.asc file in \Masm32\MasmBasic\RichMasm.exe and hit F6 to build and run it. The result:

The grid itself can be drawn if you have the exact dimensions of the window, If you take a GDI+ clock from another topic as an example, you can draw a certain number of spheres with different sizes, and then calculate the connection lines. I think it will work

I have tried to draw different things with gdiSeems everything but setpixel appears fast despite loops calling many rects ,I suspect its drawn with or without hardware acceleration on a backbuffer so it appears to be drawn instantly